REVIEW: BrainFPV RE1 & mPB
New flight controllers seem to be announced every week, the result of the current boom in drone racing. Most are simply clones of other boards with one or two adjustments, while some are either innovative or just awkward messes. In this senior prom of hits and near-misses, the BrainFPV RE1 stands ready just outside the door – ready to burst on the scene in a little less than a month. The question is will it be crowned king, or like Carrie end up covered in blood, setting the gym on fire and tearing through town like a demon? Wait, what was I talking about again? That analogy wasn’t the best… nevermind.
I’ve spent the last few weeks playing with the BrainFPV RE1 and its companion the mPB and I have to say it’s pretty cool. Even as a perpetual noob, I’ve flown everything from old 8bit Crius boards, CC3D’s and Naze32’s, up to the RMRC Dodo. The new BrainFPV combo is something else entirely – and that’s a very good thing.
The RE1 uses the STM32 F4 processor, which is a good deal faster than the one found in something like the Seriously Pro F3 flight controller. Heck, it even runs faster than other F4-based flight controllers (180MHz vs 168MHz). It’s really fast is what I’m saying. It also has an integrated OSD – Not integrated as in there is a separate set of components running MWOSD and sharing the board real estate, integrated as in directly tied to both the hardware and software. Accelerometers and gyros have also been upgraded, and the OSD fully supports 3D FPV gear such as the popular Nerdcam 3D MK2. Another difference between the RE1 and your average FC is that it is built to run dRonin, a newer firmware with a Tau Labs/OpenPilot pedigree. That could sway your opinion either way depending on how much you are willing to trust unproven software, but in my experience with it so far it is remarkably solid and fully-featured. The mPB and RE1 are stackable and directly connected for a nice clean build, and the RE1 even has a multi-protocol IR transponder system built-in. With two boards you are are few motors and ESCs away from a complete build with little to no mess of wires. Bonus: it is designed, assembled, and tested in the US of A. Booyah!
The quality of the build is superb, and just by looking at the RE1 you can tell this isn’t a cheap clone. Utilizing male and female pin headers it is meant to stack on top of the mPB using the included standoffs without any messy wires. I mounted mine in a Catalyst Machineworks Speed Addict 210-R which, due to the unusual frame design, required some creative hardware replacement as shown in my photos (I’ll go into more details in a future build review). regardless it worked out great and the result is an incredibly clean build that I can be proud of.
The mPB is made with 4oz copper and high quality components, and provides the FC with clean regulated power as well as voltage and current sensing. You can connect a 2S-4S lipo and it has both 5V and 12V outputs. The large cap in the center goes a long way towards making sure your FPV feed is noise-free! You get a filtered output with battery voltage, useful for your video transmitter, two 5V outputs and one 12V output, which is plenty to run your FPV camera and some LEDs. Did I say some LEDs? Because the RE1 supports over 1,000 LEDs which can be configured by color via the OSD. Another bonus: if you use a TBS Unify Pro 5.8GHz video transmitter you can change band, frequency, and power via the OSD as well. No more dip-switches!
Even in my unusual frame, I found the BrainFPV RE1 and mPB combo easy to work with during the install. The build is my cleanest so far, with very little actually needed for it to be complete. All you need is the RE1, mPB, motors, ESCs, a camera, VTX, and receiver. Everything is direct solder unless you want to go through all the trouble of soldering pin headers and adding weight, but you wouldn’t do that on a racer – would you? BrainFPV provides a fantastic user guide on their site that walks your through the whole process and shows you what to solder where. It’s rare to see that sort of first-party support material, and it’s a wonderful change from the days I used to spend searching RCGroups for a dead thread with half-correct information. If this doesn’t show that the team behind the RE1 want it to succeed, you should know that they also contribute regularly to the dRonin project. On my first day there was an issue getting a PPM signal to work due to a recent code change, and after contacting the BrainFPV team they had it fixed and a new software build ready within the hour. Speaking of dRonin, that was the next step of the build!
If you’ve ever used OpenPilot/LibrePilot or Tau Labs software you’ll see the resemblance immediately. If you’re coming from *flight configurators, this may take some getting used to. That isn’t to say it is difficult though, as a matter of fact it is a LOT easier than getting started with other software. The release I was using was a custom pre-release version, though the final release version will be very similar. All you need to do to get started is to run the GCS software and then connect to your flight controller. If a firmware update is required it will notify you and the process can be initiated. Once your firmware is updated you can run through the Vehicle Setup Wizard. Answer a few questions, follow a few instructions, and your quad will be ready to maiden! “But Noob, what about tuning my PIDs?” I hear you, imaginary reader, ask. Well that’s the fun part. Every see a quadcopter boogie? You’re about to.
A pretty solid tune can be achieved by utilizing dRonin’s “Autotune” feature. Now if you’ve done any research at all I’m sure you’ve heard tales about autotune going wrong, but that’s in other firmware. dRonin’s autotune actually works and is pretty fun to watch. After configuring your flight mode switch to include autotune you put your quad in as stable a hover as you can manage and initiate the tune. Your quad will then proceed to do a little shimmy-shake in the air for around 60 seconds. You retain full control over the quad during this time so you can keep it from drifting too far or, should something go wrong, drop out of the autotune routine to recover and/or disarm. Once your little buddy is all tuckered out from his jig, land and disarm. Reconnect to the GCS software and it will detect a new autotune has taken place and will ask you to review.
The GCS software does some crazy math magic or something by measuring motor and controller response timing and comparing the salvo flange to the flux capacitor, and comes back with PIDs custom tuned for your build. You can adjust sensitivity and dampening to tweak the tune, and then apply the results. After running through the process I ended up with a quad that needed only minor adjustments, mostly to rates and expos, to suit my particular style of barely not crashing. Without exaggerating, flying the RE1 after running autotune was not only one of the fastest build-to-maiden time frames ever, it was also the smoothest maiden I’ve ever experienced. Unbalanced props caused some drifting in leveling modes, but in acro/rate mode there were hardly any bad characteristics at all, and what there were was minor. Some slight oscillations at full throttle were quickly corrected by going back and adjusting the sensitivity/dampening sliders and I was back in the air. If you’re a noob with some soldering skills, this could be the racing flight controller you’ve been looking for.
Nearly everything about the BrainFPV RE1 is configurable through the OSD, and as of the last release you can also configure the TBS Unify Pro video transmitter. You can switch between 25mW, 200mW, 800mW power and also choose band and frequency. In a frame where you can’t reach the VTX dip-switches or button this is an awesome feature.
Should you need to adjust PIDs, rates, etc. or decide to forego the autotune process you can tune from scratch via the OSD. No need for a laptop or smartphone GCS app! You can also set your flight modes this way should you need to change them in the field, and even switch transponder protocols or IDs as well as LED color. One thing I do find lacking however is the inability to enable/disable OSD elements. MWOSD does this nicely, allowing you to hide elements on the fly from the menu. Hopefully they’ll work this out in the future.
That being said, you can completely customize your OSD layout via the GCS software. I found the default view to be a bit distracting with the horizon line and whatnot, so I spent some time in the GCS software customizing the HUD. You can power up your quad and then connect (PROPS OFF!) and apply changes while viewing the OSD in real-time on your FPV display. I have been told they are working on a graphical layout tool as well, which would be a welcome addition as the current interface is, well, pedestrian at best. It works, and all the pieces are there, but it doesn’t compare to the MWOSD tool.
None of these features really matter though if it doesn’t fly well, but boy does it! I meant it earlier when I said it was my smoothest maiden ever. I played with my rates a bit and adjusted my expos, and the result was my best quad so far. This is my go-to quad. This is my baby. This is the one I show off to the big guys at events. This is the one I’ll be racing this weekend. Sure there’s more to it than just the flight controller, but all your motors and ESCs are nothing without the “brain” (ooooh, I see what they did there…) and this thing is a Mensa level genius. In the hands of a noob it is a fully featured, simple to build, simple to configure, great flying flight controller. In the hands of a pro the BrainFPV RE1 is a BEAST, as evidenced by their promotional videos. It isn’t cheap at about $105 for the pair and that may scare some away, but this is an investment worth making if you are looking for a powerhouse flight controller with plenty of room to grow. As dRonin develops the RE1 value will increase, and as its value increases so too will the dRonin software grow and prosper.
Normally I’m against being an early adopter, but to all you folks out there who pre-ordered… You’re going to love this!